Two background tasks scheduled on every chat completion in
routes/chat_helpers.py — the memory/skill extraction dispatch and the
session auto-namer — are created via bare asyncio.create_task(...).
asyncio only holds a weak reference to the outer task, so the GC can
collect it mid-execution and the work silently never runs.
Add a module-private _BG_TASKS set and a _spawn_bg() helper that mirrors
WebhookManager._spawn_tracked (the pattern #3964 / #4336 established for
the webhook emitters two lines apart in the same function). Route both
call sites through it so the lifecycle owner is explicit.
Adds an AST-level guard test that fails on any bare
asyncio.create_task(...) statement in routes/chat_helpers.py to prevent
a regression — same shape as test_webhook_emitters_use_manager.py from
#4336.
The same bare pattern exists in routes/email_routes.py and
routes/cookbook_routes.py; left out of this PR per CONTRIBUTING.md's
"one fix per PR" and tracked in #4443's "Additional Information" for a
follow-up.
Wei Hong
7475779b7c